Relay-Aided Request-Aware Distributed Packet Caching for Device-to-Device Communication

To improve the data retrieval performance of device-to-device (D2D) communication, the impact from the various concentration levels of packet requests from different user equipment (UE) groups should be considered. However, few existing works incorporate this aspect in system design. In this letter, we propose a new distributed D2D relay-aided packet caching scheme, which exploits the properties of the diverse packet requests and requirements of physical link success among different UE groups. Theoretical optimal solution to the packet caching problem and several properties of its influencing factors are studied, showing that the system performance can be improved by exploiting the so-called packet request diversity. Simulation results validate our analyses and demonstrate the benefits of the proposed scheme.